From: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
this driver is used by the user-space tool:oprofile to profile linux
kernel or applications via loongson2 performance counters. you can
enable this driver via CONFIG_OPROFILE = y or m.
In loongson2, there are two performance counters, each one can count 16
events respectively. when anyone of the performance counter overflows,
an interrupt will generate and goes to the interrupt line:
MIPS_CPU_IRQ_BASE + 6, in fuloong2e, this interrupt line is exclusivly
used by perf counter, but in fuloong2f & yeeloong2f, this interrupt line
is shared by perf counter and the CPU internal north bridge(bonito64
compatiable).
NOTE: a patch should be sent to oprofile with the loongson-specific
support. otherwise, the oprofile tool will not recognize this and
complain about "cpu_type 'unset' is not valid". currently, the cpu_type
is hard-coded in arch/mips/oprofile/op_model_loongson2.c as
'mips/loongson2'
Signed-off-by: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
---
arch/mips/include/asm/mach-loongson/loongson.h | 2 +
arch/mips/include/asm/mach-loongson/machine.h | 1 -
arch/mips/loongson/common/irq.c | 26 +++-
arch/mips/loongson/fuloong-2e/irq.c | 2 +
arch/mips/loongson/fuloong-2f/irq.c | 6 +-
arch/mips/loongson/yeeloong-2f/irq.c | 6 +-
arch/mips/oprofile/Makefile | 1 +
arch/mips/oprofile/common.c | 5 +
arch/mips/oprofile/op_model_loongson2.c | 186 ++++++++++++++++++++++++
9 files changed, 227 insertions(+), 8 deletions(-)
create mode 100644 arch/mips/oprofile/op_model_loongson2.c
diff --git a/arch/mips/include/asm/mach-loongson/loongson.h b/arch/mips/include/asm/mach-loongson/loongson.h
index aaa2948..81db273 100644
--- a/arch/mips/include/asm/mach-loongson/loongson.h
+++ b/arch/mips/include/asm/mach-loongson/loongson.h
@@ -45,7 +45,9 @@ extern void mach_prepare_shutdown(void);
#define LOONGSON_REG(x) \
(*(u32 *)((char *)CKSEG1ADDR(LOONGSON_REG_BASE) + (x)))
+
#define LOONGSON_IRQ_BASE 32
+#define LOONGSON_PERFCNT_IRQ (MIPS_CPU_IRQ_BASE + 6) /* cpu perf counter */
#define LOONGSON_FLASH_BASE 0x1c000000
#define LOONGSON_FLASH_SIZE 0x02000000 /* 32M */
diff --git a/arch/mips/include/asm/mach-loongson/machine.h b/arch/mips/include/asm/mach-loongson/machine.h
index c8b83b4..80cf421 100644
--- a/arch/mips/include/asm/mach-loongson/machine.h
+++ b/arch/mips/include/asm/mach-loongson/machine.h
@@ -63,7 +63,6 @@
#if defined(CONFIG_LEMOTE_FULOONG2F) || defined(CONFIG_LEMOTE_YEELOONG2F)
#define LOONGSON_TIMER_IRQ (MIPS_CPU_IRQ_BASE + 7) /* cpu timer */
-#define LOONGSON_PERFCNT_IRQ (MIPS_CPU_IRQ_BASE + 6) /* cpu perf counter */
#define LOONGSON_NORTH_BRIDGE_IRQ (MIPS_CPU_IRQ_BASE + 6) /* bonito */
#define LOONGSON_UART_IRQ (MIPS_CPU_IRQ_BASE + 3) /* cpu serial port */
#define LOONGSON_SOUTH_BRIDGE_IRQ (MIPS_CPU_IRQ_BASE + 2) /* i8259 */
diff --git a/arch/mips/loongson/common/irq.c b/arch/mips/loongson/common/irq.c
index 79ae697..a2c3196 100644
--- a/arch/mips/loongson/common/irq.c
+++ b/arch/mips/loongson/common/irq.c
@@ -71,6 +71,30 @@ static struct irqaction cascade_irqaction = {
.name = "cascade",
};
+/*
+ * fuloong2f and yeeloong2f share the cpu perf counter interrupt and the north
+ * bridge interrupt in IP6, so, the ip6_irqaction should be sharable.
+ * otherwise, we will can not request the perf counter irq(setup the perf
+ * counter irq handler) in op_model_loongson2.c.
+ */
+
+#if defined(CONFIG_OPROFILE) && \
+ defined(CONFIG_LEMOTE_FULOONG2F) || defined(CONFIG_LEMOTE_YEELOONG2F)
+irqreturn_t ip6_action(int cpl, void *dev_id)
+{
+ return IRQ_HANDLED;
+}
+
+static struct irqaction ip6_irqaction = {
+ .handler = ip6_action,
+ .mask = CPU_MASK_NONE,
+ .name = "cascade",
+ .flags = IRQF_SHARED,
+};
+#else
+#define ip6_irqaction cascade_irqaction
+#endif
+
void __init arch_init_irq(void)
{
/*
@@ -104,7 +128,7 @@ void __init arch_init_irq(void)
bonito_irq_init();
/* setup north bridge irq (bonito) */
- setup_irq(LOONGSON_NORTH_BRIDGE_IRQ, &cascade_irqaction);
+ setup_irq(LOONGSON_NORTH_BRIDGE_IRQ, &ip6_irqaction);
/* setup source bridge irq (i8259) */
setup_irq(LOONGSON_SOUTH_BRIDGE_IRQ, &cascade_irqaction);
}
diff --git a/arch/mips/loongson/fuloong-2e/irq.c b/arch/mips/loongson/fuloong-2e/irq.c
index 00e95ad..c01e375 100644
--- a/arch/mips/loongson/fuloong-2e/irq.c
+++ b/arch/mips/loongson/fuloong-2e/irq.c
@@ -40,6 +40,8 @@ inline void mach_irq_dispatch(unsigned int pending)
{
if (pending & CAUSEF_IP7)
do_IRQ(LOONGSON_TIMER_IRQ);
+ else if (pending & CAUSEF_IP6) /* perf counter loverflow */
+ do_IRQ(LOONGSON_PERFCNT_IRQ);
else if (pending & CAUSEF_IP5)
i8259_irqdispatch();
else if (pending & CAUSEF_IP2)
diff --git a/arch/mips/loongson/fuloong-2f/irq.c b/arch/mips/loongson/fuloong-2f/irq.c
index 571aeb3..3627dda 100644
--- a/arch/mips/loongson/fuloong-2f/irq.c
+++ b/arch/mips/loongson/fuloong-2f/irq.c
@@ -34,9 +34,9 @@ inline void mach_irq_dispatch(unsigned int pending)
{
if (pending & CAUSEF_IP7)
do_IRQ(LOONGSON_TIMER_IRQ);
- else if (pending & CAUSEF_IP6) { /* North Bridge, Perf counter */
- do_IRQ(LOONGSON_PERFCNT_IRQ);
- bonito_irqdispatch();
+ else if (pending & CAUSEF_IP6) {
+ do_IRQ(LOONGSON_PERFCNT_IRQ); /* Perf counter overflow */
+ bonito_irqdispatch(); /* North Bridge */
} else if (pending & CAUSEF_IP3) /* CPU UART */
do_IRQ(LOONGSON_UART_IRQ);
else if (pending & CAUSEF_IP2) /* South Bridge */
diff --git a/arch/mips/loongson/yeeloong-2f/irq.c b/arch/mips/loongson/yeeloong-2f/irq.c
index 571aeb3..3627dda 100644
--- a/arch/mips/loongson/yeeloong-2f/irq.c
+++ b/arch/mips/loongson/yeeloong-2f/irq.c
@@ -34,9 +34,9 @@ inline void mach_irq_dispatch(unsigned int pending)
{
if (pending & CAUSEF_IP7)
do_IRQ(LOONGSON_TIMER_IRQ);
- else if (pending & CAUSEF_IP6) { /* North Bridge, Perf counter */
- do_IRQ(LOONGSON_PERFCNT_IRQ);
- bonito_irqdispatch();
+ else if (pending & CAUSEF_IP6) {
+ do_IRQ(LOONGSON_PERFCNT_IRQ); /* Perf counter overflow */
+ bonito_irqdispatch(); /* North Bridge */
} else if (pending & CAUSEF_IP3) /* CPU UART */
do_IRQ(LOONGSON_UART_IRQ);
else if (pending & CAUSEF_IP2) /* South Bridge */
diff --git a/arch/mips/oprofile/Makefile b/arch/mips/oprofile/Makefile
index bf3be6f..d039d6b 100644
--- a/arch/mips/oprofile/Makefile
+++ b/arch/mips/oprofile/Makefile
@@ -15,3 +15,4 @@ oprofile-$(CONFIG_CPU_MIPS64) += op_model_mipsxx.o
oprofile-$(CONFIG_CPU_R10000) += op_model_mipsxx.o
oprofile-$(CONFIG_CPU_SB1) += op_model_mipsxx.o
oprofile-$(CONFIG_CPU_RM9000) += op_model_rm9000.o
+oprofile-$(CONFIG_CPU_LOONGSON2) += op_model_loongson2.o
diff --git a/arch/mips/oprofile/common.c b/arch/mips/oprofile/common.c
index 3bf3354..fd52bf6 100644
--- a/arch/mips/oprofile/common.c
+++ b/arch/mips/oprofile/common.c
@@ -16,6 +16,7 @@
extern struct op_mips_model op_model_mipsxx_ops __attribute__((weak));
extern struct op_mips_model op_model_rm9000_ops __attribute__((weak));
+extern struct op_mips_model op_model_loongson2_ops __attribute__((weak));
static struct op_mips_model *model;
@@ -93,6 +94,10 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
case CPU_RM9000:
lmodel = &op_model_rm9000_ops;
break;
+
+ case CPU_LOONGSON2:
+ lmodel = &op_model_loongson2_ops;
+ break;
};
if (!lmodel)
diff --git a/arch/mips/oprofile/op_model_loongson2.c b/arch/mips/oprofile/op_model_loongson2.c
new file mode 100644
index 0000000..876674f
--- /dev/null
+++ b/arch/mips/oprofile/op_model_loongson2.c
@@ -0,0 +1,186 @@
+/*
+ * Loongson2 performance counter driver for oprofile
+ *
+ * Copyright (C) 2009 Lemote Inc. & Insititute of Computing Technology
+ * Author: Yanhua <yanh@xxxxxxxxxx>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ */
+#include <linux/init.h>
+#include <linux/oprofile.h>
+#include <linux/interrupt.h>
+#include <linux/smp.h>
+#include <linux/spinlock.h>
+#include <linux/proc_fs.h>
+#include <linux/uaccess.h>
+
+#include <irq.h>
+#include <loongson.h> /* LOONGSON_PERFCNT_IRQ */
+#include "op_impl.h"
+
+/*
+ * a patch should be sent to oprofile with the loongson-specific support.
+ * otherwise, the oprofile tool will not recognize this and complain about
+ * "cpu_type 'unset' is not valid".
+ */
+#define LOONGSON_CPU_TYPE "mips/loongson2"
+
+#define LOONGSON_COUNTER1_EVENT(event) ((event & 0x0f) << 5)
+#define LOONGSON_COUNTER2_EVENT(event) ((event & 0x0f) << 9)
+
+#define LOONGSON_PERFCNT_EXL (1UL << 0)
+#define LOONGSON_PERFCNT_KERNEL (1UL << 1)
+#define LOONGSON_PERFCNT_SUPERVISOR (1UL << 2)
+#define LOONGSON_PERFCNT_USER (1UL << 3)
+#define LOONGSON_PERFCNT_INT_EN (1UL << 4)
+#define LOONGSON_PERFCNT_OVERFLOW (1ULL << 31)
+
+/* Loongson2 performance counter register */
+#define read_c0_perflo() __read_64bit_c0_register($24, 0)
+#define write_c0_perflo(val) __write_64bit_c0_register($24, 0, val)
+#define read_c0_perfhi() __read_64bit_c0_register($25, 0)
+#define write_c0_perfhi(val) __write_64bit_c0_register($25, 0, val)
+
+static struct loongson2_register_config {
+ unsigned int ctrl;
+ unsigned long long reset_counter1;
+ unsigned long long reset_counter2;
+ int cnt1_enable, cnt2_enable;
+} reg;
+
+DEFINE_SPINLOCK(sample_lock);
+
+static char *oprofid = "LoongsonPerf";
+static irqreturn_t loongson2_perfcount_handler(int irq, void *dev_id);
+/* Compute all of the registers in preparation for enabling profiling. */
+
+static void loongson2_reg_setup(struct op_counter_config *cfg)
+{
+ unsigned int ctrl = 0;
+
+ reg.reset_counter1 = 0;
+ reg.reset_counter2 = 0;
+ /* Compute the performance counter ctrl word. */
+ /* For now count kernel and user mode */
+ if (cfg[0].enabled) {
+ ctrl |= LOONGSON_COUNTER1_EVENT(cfg[0].event) |
+ LOONGSON_PERFCNT_INT_EN;
+ if (cfg[0].kernel)
+ ctrl |= LOONGSON_PERFCNT_KERNEL;
+ if (cfg[0].user)
+ ctrl |= LOONGSON_PERFCNT_USER;
+ reg.reset_counter1 = 0x80000000ULL - cfg[0].count;
+ }
+
+ if (cfg[1].enabled) {
+ ctrl |= LOONGSON_COUNTER2_EVENT(cfg[1].event) |
+ LOONGSON_PERFCNT_INT_EN;
+ if (cfg[1].kernel)
+ ctrl |= LOONGSON_PERFCNT_KERNEL;
+ if (cfg[1].user)
+ ctrl |= LOONGSON_PERFCNT_USER;
+ reg.reset_counter2 = (0x80000000ULL - cfg[1].count);
+ }
+
+ if (cfg[0].enabled || cfg[1].enabled)
+ ctrl |= LOONGSON_PERFCNT_EXL;
+
+ reg.ctrl = ctrl;
+
+ reg.cnt1_enable = cfg[0].enabled;
+ reg.cnt2_enable = cfg[1].enabled;
+
+}
+
+/* Program all of the registers in preparation for enabling profiling. */
+
+static void loongson2_cpu_setup(void *args)
+{
+ uint64_t perfcount;
+
+ perfcount = (reg.reset_counter2 << 32) | reg.reset_counter1;
+ write_c0_perfhi(perfcount);
+}
+
+static void loongson2_cpu_start(void *args)
+{
+ /* Start all counters on current CPU */
+ if (reg.cnt1_enable || reg.cnt2_enable)
+ write_c0_perflo(reg.ctrl);
+}
+
+static void loongson2_cpu_stop(void *args)
+{
+ /* Stop all counters on current CPU */
+ write_c0_perflo(0);
+ memset(®, 0, sizeof(reg));
+}
+
+static irqreturn_t loongson2_perfcount_handler(int irq, void *dev_id)
+{
+ uint64_t counter, counter1, counter2;
+ struct pt_regs *regs = get_irq_regs();
+ int enabled;
+ unsigned long flags;
+
+ /*
+ * LOONGSON2 defines two 32-bit performance counters.
+ * To avoid a race updating the registers we need to stop the counters
+ * while we're messing with
+ * them ...
+ */
+
+ /* Check whether the irq belongs to me */
+ enabled = reg.cnt1_enable | reg.cnt2_enable;
+ if (!enabled)
+ return IRQ_NONE;
+
+ counter = read_c0_perfhi();
+ counter1 = counter & 0xffffffff;
+ counter2 = counter >> 32;
+
+ spin_lock_irqsave(&sample_lock, flags);
+
+ if (counter1 & LOONGSON_PERFCNT_OVERFLOW) {
+ if (reg.cnt1_enable)
+ oprofile_add_sample(regs, 0);
+ counter1 = reg.reset_counter1;
+ }
+ if (counter2 & LOONGSON_PERFCNT_OVERFLOW) {
+ if (reg.cnt2_enable)
+ oprofile_add_sample(regs, 1);
+ counter2 = reg.reset_counter2;
+ }
+
+ spin_unlock_irqrestore(&sample_lock, flags);
+
+ write_c0_perfhi((counter2 << 32) | counter1);
+
+ return IRQ_HANDLED;
+}
+
+static int __init loongson2_init(void)
+{
+ return request_irq(LOONGSON_PERFCNT_IRQ, loongson2_perfcount_handler,
+ IRQF_SHARED, "Perfcounter", oprofid);
+}
+
+static void loongson2_exit(void)
+{
+ write_c0_perflo(0);
+ free_irq(LOONGSON_PERFCNT_IRQ, oprofid);
+}
+
+struct op_mips_model op_model_loongson2_ops = {
+ .reg_setup = loongson2_reg_setup,
+ .cpu_setup = loongson2_cpu_setup,
+ .init = loongson2_init,
+ .exit = loongson2_exit,
+ .cpu_start = loongson2_cpu_start,
+ .cpu_stop = loongson2_cpu_stop,
+ .cpu_type = LOONGSON_CPU_TYPE,
+ .num_counters = 2
+};
--
1.6.2.1
